Process for hydrocarbon boiling point reduction



Sept. 23, 1958 c. H. o. BERG 2,853,438

l l PROCESS FOR HYDROCARBON BOILING POINT REDUCTION 'Filed March 29,1952 ,www

United States Patent O PROCESS FOR HYDROCARBON BOILING POINT REDUCTIONClyde H. O. Berg, Long Beach, Calif., assignor to Union Oil Company ofCalifornia, Los Angeles, Calif., a corporation of California vApplication March 29,1952, Serial No. 279,403 17 Claims. (Cl. 196-52)This invention `relates generally to the conversion of hydrocarbons andin particular relates to a hydrocarbon contacting process to effect aboiling point reduction simultaneously with, if desired, otherhydrocarbon conversion processes. Specifically, it relates to animproved .process and apparatus for the treatment of hydrocarbons.boiling above labout 400 F. to effect a maximum pro- .catalyticactivity for hydrocarbon conversions. In Athe thermal processes arelatively heavy hydrocarbon fraction is heated to its reactiontemperature bypassage through a heater wherein at least a partialdecomposition to more volatile products is eifected and generally withthe simultaneous production of heavy hydrocarbonaceous residualmaterials referred to as coke. In the catalytic processes thehydrocarbon feed is heated generally to a somewhat lower temperature andis contacted with granular solids having catalytic activity promotingthe desired hydrocarbon conversion reaction.

In these conventional processes all of the materials introduced as feedand which are not converted to residual materials such as coke pass atsubstantially the same velocity through the reaction or conversion zone.VThus, any desired product which is formed initially is neverthelesssubjected to further and unneeded treatment during itspassage throughthe remainder of the reaction zone and whereby a partial degradation ofthese materials to undesirable products invariably takes place. In spiteof the fact that the gasoline range hydrocarbons thermally decompose atroughly only half the rate at which a gas oil range hydrocarbon does,still a substantial proportion of the gasoline hydrocarbons are thuslost and an unduly high gas and coke production results.

In addition, even under recycling conditions, the unreacted fraction ofthe feed material becomes more and more aromatic or refractory innaturevand becomes succeedingly difficult to convert under the existingtemperature and pressure conditions. Thus, a certain amount of thehydrocarbon feed cannot be converted into the products having thedesired boiling range.

The principal disadvantages, therefore, vof the conventional processesmay be summarized as: rst, a substantial proportion of the hydrocarbonfeed is converted to coke and gas; second, the residual unreactedmaterial becomes refractory precluding operations processing thehydrocarbon feed to extinction; third, desirable boiling vrangehydrocarbons initially formed are at least partially Mice degradatedbefore they can be removed from-the reaction zone; and fourth, aselective removal of the desired products as formed is not possible.

.The process land apparatus of the present invention successfullyovercomes the aforo-mentioned disadvantages and comprises an improvedoperation in which a given hydrocarbon feed stock of relatively highboiling point may be converted at high efficiency into a productfraction boiling in thegasoline hydrocarbon range -withanabsoluteminimum of gas and coke production and w-hich also may, ifdesired, simultaneously subjecteither the hydrocarbon feed or the.desirable hydrocarbons formed as products or both to theotherhydrocarbon conversion reactions such as those referred to above.

lt is therefore a primary object of this inventionto provide an improvedprocess for effecting the boiling .point reduction of hydrocarbons atimproved etliciency wherein a relatively long concurrent contact ofhydrocar- ,bon feed and granular solids is effected under reactionconditions of temperaure and pressure followed by a :rapid removal ofthe hydrocarbon products boiling in the desired range effected by arelatively short countercurrent Contact of such products with solidsprior to removal from the reaction zone.

Another object of this invention 'is to provide an improved hydrocarbonboiling point reduction process which comprises concurrently contactinga moving bed of heated lgranular solids with a liquid hydrocarbon to beconverted in a. reaction zone while maintaining in this zone a coun---tercurrent llow of gas which sweeps the hydrocarbon prod- ,ucts ofvreduced boiling point countercurrently through the reaction zone forremoval therefrom at high velocity to prevent the desired hydrocarbonfraction from 'being decomposed.

It is a further object of this invention to provide an improved processas stated in the foregoing objects in which the countercurrent flow ofgas maintained in the reactionrzone contains hydrogen to further enhancethe increased yield of hydrocarbons boiling in the desired range and toinhibit the formation of undesired products .such as coke and aromaticrefractoryresidual hydrocarbons.

It is an additional object of this invention to provide :the boilingpoint reduction process mentioned above in `the foregoing objects inwhich a moving bed of granular hydrocarbon cracking catalyst isemployed.

It is a further object of this invention tc provide a process forhydrocarbon conversion which etects a hydrocarbon boiling pointreduction according to the objects above simultaneously with aneffective desulfurization, reforming, denitrogenation, isomerization,aromatization, hydrogenation, and/or dehydrogenation whereby either thefeed hydrocarbons or the product hydrocarbons y or both are furtherimproved and upgraded.

It is an additional object to provide in such aprocess the use of amixed catalyst whereby a hydrocarbon boiling point reduction and one ormore of the named hydrocarbon conversion reactions are effectedcatalytically.

Av further specic object of this invention is to provideaprocess forcatalytically cracking petroleum hydrocarbon fractions and recycledunconverted hydrocrabons boiling above about 400 F. by contact with ahydrocarbon cracking catalyst in the presence of a recycle gascontaining hydrogen and flowing countercurrent to the catalyst flowwhereby the hydrocarbons thus treated may be converted to extinction tohydrocarbon products boiling in the gasoline range.

Another'object of this invention is to provide an improved -apparatusadapted to effect the foregoing objects.

' Other objects' and advantages of the present invention.

3 will become apparent to those skilled in the art as the descriptionand illustration thereof proceeds.

Briefly, the present invention comprises a continuoushydrocarbon-granular solids contacting process for the boiling pointreduction of hydrocarbon fractions wherein a liquid hydrocarbon feed iscontacted with a moving established by employing a liquid feed streamentering mass of granular solids and passes concurrently therewith y atleast part way through a reaction zone under reaction conditions oftemperature and pressure and in the presence of a countercurrent flow ofvapor containing the hydrocarbon products of the process.. Liquidhydrocarbons are brought into contact by spraying, or are otherwisemixed with the moving bed of heated granular solids and are retainedthereon by adsorption and/or wetting depending on the physicalcharacteristics of the solid materials. The heated solids are thus atleast partly saturated with liquid hydrocarbon feeds. The hydrocarbonfeed in normal operation does not run down through the solids bed,especially at high solids to feed ratios, but it may to some extent atthe lower ratios. Ordinarily the feed oil, at least partly saturatingthe solids, is carried by the moving bed of solids at least part waydown through the reaction or soaking Zone maintained under conversionconditions of pressure and temperature. During this time, the boilingpoint reduction and hydrocarbon cracking reactions take place on thesaturated solids with the formation of hydrocarbon products of increasedvolatility and lower boiling point. Because of the increased volatility,the products are rapidly vaporized substantially as soon as they areformed in contact with the granular solids and are rapidly removed fromthe reaction zone by means of a counter-current gas and vapor flowmaintained at a highvvelocity therein. Heat is introduced to thereaction zone in the heated granular solids and in the heatedcountercurrent flow of vapor passing through the solids bed whereby heatof product vaporization is supplied. The relatively heavy hydrocarbonsintroduced as feed remain in contact with the granular solids as long asis necessary to form products of sucient volatility to escape from theliquid phase established on the granular solids. The granular solidsmove relatively slowly down through the reactor and the vapor phase canbe made to move therethrough as fast as desired. The feed hydrocarbonsof relatively high boiling point pass concurrently with the solids untilmore volatile products are formed and these products are swept rapidlycountercurrent to the granular solids through the reaction zone and areremoved therefrom at a rate suicient to eliminate further boiling pointreduction reactions.

In the case where additional hydrocarbon conversion reactions aredesirable, the granular solids may be selected to catalytically enhanceeither one or both of the boiling point reducing reaction and thedesired additional reaction and the rate at which the desiredhydrocarbon products are passed countercurrently through the reactionzone may be further varied `according to the required conditions of theadditional conversion reaction.

The process employs a downwardly moving compact bed of granular solidswhich may or may not have catalytic activity. Preferably, Ia catalystsuch as any one of the well-known hydrocarbon cracking catalysts isernployed to increase the rate of the boiling point reduction However,in the treatment of hydrocarbon feed stocks catalytically inactivegranular solids, such yas reaction.

coke, aluminum oxide, high melting point metals, ctc.,

1 may be employed to effect a noncatalytic hydrocarbon conversion on theextended surface area provided by the heated granular solids. Followingthe passage of the granular solids through the reaction zone they arepassed through a regeneration zone and subjected to the action of anoxygen-containing gas for reheating and regeneration in the case ofcatalysts and returned to contact further quantities of the hydrocarbonto be processed.

The simultaneous countercurrent and concurrent flow i' o f hydrocarbonsrelative to the granular solids ow is aceous products in the reactionzone.

near the top of the reaction zone, the introduction of a recycle gasnear the bottom 'and removal of the desired hydrocarbon products and therecycle gas in the vapor phase from near the top of the reaction zone.Thus, the hydrocarbon feed flows in the liquid phase concurrently withthe solids through the reaction zone and the hydrocarbon products areremoved in the vapor phase countercurrent to the solids ow. If desired,product removal may be effected above the feed inlet point thussubjecting the product to the action of fresh solids whereby the heavieror higher boiling fractions may be absorbed and returned for furtherreaction and/or the product may be reacted in the presence of the freshcatalyst.

The hydrocarbon product stream is removed from the reaction zone yandfractionated for the separation of gas and liquid hydrocarbons boilingin the desired temperature range from the unreacted hydrocarbons havingboiling points greater than the end point of the desired product. Theunreacted hydrocarbons, which do not have the aromatic and refractorycharacteristics of conventional hydrocarbon boiling point reductionreactions for reasons described below, are recirculated forreintroduction with fresh feed into the reaction zone. At least part ofthe gas recovered from the reaction zone eluent may be fractionated ifdesired and a. stream thereof, preferably containing hydrogen, isintroduced into the bottom of the reaction zone to sweep out thehydrocarbon products countercurrently as they are formed. The desiredhydrocarbons may be subject to further fractionation and are removedfrom the process as one or more product streams.

The recycle gas contains substantial quantities of hydrogen formed inthe cracking and boiling point reduction reactions. Even in the absenceof other hydrocarbon conversion processes such as aromatization,desulfurization, and other such reactions named above, this hydrogen hasbeen found to have an extremely benecial effect upon the boiling pointreduction reactions in this process whereby highly increased liquidyields are obtained. First, this hydrogen recycle sweep gas represses toa large extent the formation of heavy non-volatile hydrocarbon- Second,it represses the formation of aromatic refractory residual hydrocarbonswhich ordinarily prevent recycling hydrocarbons to extinction in theconventional cracking processes. Third, it effectively stripshydrocarbons from the granularsolids just prior to their removal Afromthe reaction zone keeping the liquid yield at a high value. Fourth, thehydrogen 4and the product hydrocarbons are exposed to countercurrentreaction conditions in the presence of a catalyst to further upgrade andimprove the product hydrocarbons. Fifth, a rapid removal of the producthydrocarbons of desired boiling range results precluding productdegradation. Sixth, the great difference in the boiling point betweenthe hydrogen and the hydrocarbon products simplify hydrogen recovery`and recirculation.

The present invention will be more clearly understood by reference tothe accompanying drawing which is described in connection with thecatalytic cracking of hydrocarbons boiling in the gas oil range in thepresence of a cracking catalyst according to the principles of thislnvention.

Referring now particularly to the drawing, a How diagram is given whichalso indicates in cross section elevation some of the structural"details of the reactor and regenerator.

In the drawing, the hydrocarbon to be converted is l passed through line10 and combined with a recycle feed. stream lis passed through heatercoil 24 wherein it The reactor feed is in the liquid phase and isdistributed ontoand to at leastpartly saturate a downwardly moving bedof granular solid material circulated through the reactor andregenerator vessels in a continuous stream. Granular solids areintroduced into the reactor via line 40 from the bottom of theregenerator. The granular solids; subsequently pass downwardly throughseparator zone 42 through line 44 provided withsolids ow control means,46. `The -solids pass downwardly through reactor xvessel 48 as a compactmoving bed, Near the bottom of the reactor48 is provided reciprocatingsolids feedermeans S0 whereby a uniform downward ow of solids ismaintained throughout the cross sectional area of the reactor vessel.means of line 52 controlled by valve 54 and are introduced intoinduction `chamberS. vA conveyance fluid f under pressure is introducedthereinto by means of line 58 controlled by valve 60. The granularsolids flow by gravity and the forces generated by the depressuringconveyance fluid downwardly from chamber 56 into spent solids conveyanceconduit 62. The conveyance uid depressures through the conveyanceconduit concurrently with-a ow of compact unfluidized granular spentsolids intorthe top of regenerator vessel 64. Thrust plate 66 withinseparator chamber 68 applies a thrust force to the discharge of solidsfrom conduit 62 thereby maintaining'the solids'during conveyance insubstantially compact untluidized form, a condition wherein the bulk orapparent density in pounds of solids per cubic feet of occupied volumeis the same during conveyance as the density of the granular solids inthe moving beds passing through reactor vessel 48 or regenerator Vessel68.

Granularfsolids are removed by Thel spent granular solids passdownwardlyas a compact movingv bed through the regenerator vessel 64 whereinthesolids are contacted by an oxidizing regeneration gas thereby removingresidual hydrocarbonaceous deposits on the granular solidsformingregenerated andl heated solids. Air is introduced through line 70 at arate controlled by valve 72 together with recirculated flue gasflowingthrough line 74 controlled by valve 76. This regeneration gas mixture isintroduced into regeneration gas engaging zone 78, passes in directcontact with'the granular solids burning the hydrocarbonaceous deposittherefrom, and the flue gases formed are removed from ue gas disengagingsection 80 through line 82. "These gases may be partly disposed of to astack and partthereof may be recirculated for dilution of theRegenerated solids pass downwardly from regeneration zone 84 intostripping zone 86 wherein they are p countercurrently contacted bystripping steam introduced through line 88 controlled by valve 90 intostripping steam engaging zone 92. The stripping steam passes partly intoregeneration Zone 84 removing flue gas therefrom and partly with theregenerated solids from the regeneration column via line 94 at a ratecontrolled by valve 96.

The granular solids are then passed into regeneratedv solids inductionchamber 98 into which is introduced a conveyance uid under pressurethrough line 100 controlledv by valve 102. The granular solids and thecon.

granularsolids:employedforv contacting the hydrocarbons to be convertedisestablished., k

The conveyanceconduits 40 and 62,- beinglled with moving compact porousmasses of granular solids, have a relatively high pressure `drop of:greater .than about 0.1 p. s. i. g. per foot of length, the actualvalue depend, ing upon the physical characteristics 4of the solids.Thus,

these conveyance conduits effectively seal the reactor and regeneratorvessels from each other without requiring the lengthy sealing legsconventionally employed and.,

the tall supporting structures therefore required.

Referring to reactor 48, theV liquid hydrocarbon feed,

introduced either to distributors 36 yor 38, saturates the moving bed ofhot catalystv with liquid hydrocarbons.

The thus saturated solids pass downwardly through primary and secondaryreaction lzones"106 and 108 and, through intermediate productdisengaging-zone 110 into.v tertiary reaction and soaking zone 112. Thegranular solids subsequentlypass through recycle. gasengagingkr zone114, stripping zone 116, stripping gas engaging zone 118, and aresubsequently removed' as described from r..

the bottom of the reactor.

In the operation of reactor 48 a number of modifican tions existrelative to the particular point or points of feed induction andrreactor effluent removal. In all of these ycases the reactor feed is aliquid vwhich is in-l troduced onto the downwardly movingbed of solidsfand moves concurrently therewith downwardly through the various zones ofthe vessel. Subsequently, upon `conversion of the feed to lower -boilingpoint materials,

a countercurrent'ow thereof together with the recycle.

gas'is maintained upwardly through the reactor to one or moreof theproduct outlet points. The reactor efuentis then treated in a mannerdescribed below. f

reactor48 vthrough line 120 controlled by valve 122.l

In another modication with the feedtotally introduced through line 30,thereactor effluent'is withdrawn from disengaging zone 110 through line124 controlledby valve 126. In this modification, a certain amount ofreaction time is provided in primary and secondary re-l action zones 106and =108 before product withdrawal is made, thus'decreasing somewhatthedirect recycling-of uids from the inlet to the` outletof the reactor andalso shortening the product-solids contact time. VAny products formed inzones 106 and 108 are drawn concurrently therethrough and removedthrough 'line 124 -with other" products.

In another modificationwith the totalfeed being introducedthrough line30, partftof the product'mayvbe` withdrawn through line `with theremainder of the product being withdrawn through line 124.

ln another modification of the present invention, the

reactor feed is totally introduced through line 28 and is brought intocontact with the moving solids by means of distributor 36. The solids,saturatedy with feed,fpass downwardly as a moving bed from distributor36.v The countercurrent ow of recycle gas carries the hydrocarbonproducts countercurrently through zones 112,

108 and 106 for removal through yline 120 controlled by` vvalve 122 atthe top of the'column. This type of operaf tion permits the contactingof the hydrocarbon productsr and'recycle gas with fresh solids in zone106 effectively adsorbing and retaining the higher boiling and lesseffec-,-

tively treated hydrocarbon fractions for returnwith. the bed of solidsinto the lower source. of the reactor. A minimum of feed bypassingresults and is an operation which is particularly effective when anadditional hydrocarbon conversion such as any one or more of those namedabove is simultaneously carried out.

ln another modification with the reactorfeed entering throughdistributor 36, the reactor effluent is withdrawn fromV disengaging zone110 through line 124. Such a procedure effectively reduces the contacttime which is advantageous when treating certain hydrocarbon feed stockswhich are relatively easy to process in an apparatus such as that shownin the `drawing designed for treating a wide variety of materials.

In still another modification with the reactor feed entering `throughdistributor 36, the reactor eluent may be partly withdrawn through line124 and the remainder be removed through line 120.

The other modifications involving reactor feed introductionsimultaneously through distributors 36 and 38 are obvious from thediscussion above.

The reactor effluent passes, after removal from reactor 48 following anyof the procedures or a combination thereof described above, through line128. This stream is split and passed partly through reactor feedinterchanger 22 by means of line 130, and the remaining part is passedthrough recycle gas interchanger 132 through line 134. The partiallycooled reactor effluent, resulting from combining the split streams, ispassed'through line 36 through efuent cooler 138 which reduces theefliueut to near atmospheric temperature. The partially condensedreactor efuent is introduced through line 140 into separator vessel 142.The uncondensed portion passes there; from through line 144 and throughrecycle gas absorber 146 countercurrent to an absorption oil. Thepressure conditions and the oil to gas ratio maintained in absorber 146are suflicient to absorb normally liquid hydrocarbons present inthe gasas well as the C3 and C4 hydrocarbons together with a substantialproportion of C1 and C2 hydrocarbons if desired. The unabsorbed leangas, con taining a substantial proportion of hydrogen, is removed fromabsorber 146 through line`148 and is recycled throughline 150, preheatedin interchanger 132, further heated in heater coil 152, and introducedthrough line 154 into recycle gasengaging zone 144 iu the reactor tointroduce heat and maintain the temperature of the soaking zone.Temperature conditions in the reactor are often such as to provide a netproduction of hydrogen and a suicient amount of the recycle gas maybebled olf through line 156 at a rate controlled by valve 158 therebymaintaining the desired quantity and rate of recycle gas in the system.In other cases, make-up hydrogen is added to the recycle.

The rich absorption oil is removed through line 160 from absorber 146,preheated in exchanger 162V and introduced through lin'e 164 into richoil stripper 166.

Steam or other stripping gas maybe introduced through line 168controlled by valve 170 or the stripper may be head condenser 174 forcooling and partial condensation. The cooled mixtureis passed intoseparator 176 from which the net make gas is removed through line 178controlled by valve 180 which may be a back pressure regulator. Thecondensate may be partly returned through line 182 to stripper 166 forreiiux and the remainder is passed through line 184 ata rate controlledby valve 186 into gasoline distillation column 18S as described below.

Returning to separator 142, the condensed portion of the reactor eiuentis removed therefrom through line 90, is pumped therefrom by means ofpump 190 through line .192 controlled by valve 194 which in turn isactuated by level controller 196. This liquid stream is combined withthe condensate flowing in line 184 and the mixture is preheated inpreheater 198 and is introduced for distillation into distillationcolumn 188.

Distillation column 188 produces as an overhead product a hydrocarbonfraction having the desired maximum boiling point which, for example,may be 400 F. end point gasoline. The overhead vapor ows through line200 through condenser 202 into separator 204. Any gases remaininguncondensed are removed through line 8 .206 controlled by valve 208. Thecondensate is employed 1n part as reflux in column 188 flowing throughline 210 while the remainder ows as a product from the process throughline 212 controlled by valve 214.

Those hydrocarbon materials boiling above the vdesired end point areremoved as bottoms from column 188 through line 216. Part of thesematerialsv are passed through line 21S, vaporized in reboiler 220 andthe vapors passed through line 22 into the bottom of column 188.

The remaining part is recycled through line l12 and comninedfcrretreatment with the fresh feed owing through ine 10.

Thus, a complete cyclical hydrocarbon conversion process having uniquereaction and conversion features is provided. The major proportion ofthe feed is converted to a product having certain desired boiling range.A small amount of make gas is removed as. a product through line 178 anda small quantity of coke is burned from the granularsolids inregenerator 64.

Following the above general description of the process, operating dataare given below indicating specific procedures and conditions for thevarious hydrocarbon conversion processes which may be carried outaccording to the principles of this invention.

The hydrocarbon feed stocks suitable for conversion to products havinglower boiling points in the process of the present invention includehydrocarbon naphthas, gas oils, whether straight-run or cracked, and theheavier residual type oils etc. Specifically, straight-run and/orcracked gas oil boiling above 400 F. comprises an excellent feed stockfor the production of gasoline range hydrocarbons.

Preferably, the feed stock is preheated to temperatures of the order of500 F. to 750 F. but inthose cases when higher catalyst to oil weightratios of the order of from 3 to l5 are employed, cold liquid feed maybe introduced directly onto the hot regenerated granular solidsintroduced into the reactor.

The type of granular solids employed in the process depends, of course,upon the process desired to be carried out. With catalytic cracking ofheavy gasolines, gas oil and heavier hydrocarbons, cracking catalystssuch as acid treated natural clay, silica-alumina synthetic beadcatalyst, and especially the synthetic bead catalyst containing about0.005% by weight of chromium constitute excellent catalysts in theprocess of this invention.

When a reforming or aromatization or dehydrogenation of the feed stockand/or the more volatile products produced therefrom is desired, acatalyst may be employed comprising chromium oxide, molybdenum trioxide,or cobalt molybdate.

reactions may be employed. These catalysts preferably are supported on acarrier such as aluminum oxide, or they may be impregnated directly uponthe catalyst having the cracking activity, or a mixture of cracking andreforming catalysts may be used.

When a simultaneous desulfurization is to be carried out, the catalystpreferably comprises cobalt molybdate or mixtures of COO and M003. Thesecatalysts are also satisfactory for the catalytic denitrogenation of thefeed stock or the products produced.

The catalyst to oil ratio as measured from the relative weights ofcatalyst and oil` introduced into the reactor vary, of course, accordingto the particular reaction to be carried out. ln general, values of fromabout 0.5 to 15.0 may be employed with preferable values being betweenabout 1.0 and 5.0 for catalytic cracking alone. The liquid hourly spacevelocity (LHSV) at which the product is removed in the recycle gas isbelow about 1.0, preferable values being between about 0.005 and 0.5.These catalyst to oil ratios and LHSV values also apply to the otherprocesses named above.

One essential step in the process is the countercurrent gas recycleemployed in the reactor. The quantity of this Catalysts comprisingmixtures of CoO` and M003 Vor the other well-known catalysts for theserecycle may be between about 50 and 10,000 s. c. f./ barrel of feed.`The' actual values depend largelyy upon the i nature of hydrocarbonconversion process carried out together with the boiling point reductionseparation. Re* cycle rates of between 500 and 2,000 s. c. f /barrel arepreferred for straight catalytic cracking, between about 1000 and 4000s. c. f./barrel for simultaneous cracking and reforming, and betweenabout 750 and 3000 s. c. f./ barrel for simultaneous cracking anddesulfurization.

Therecycle gas employed preferably contains a substantial quantity ofhydrogen. The actual concentration of hydrogen in the recycle gas varieswith different processes and with different feedstocks. The recycle gasmay contain as little as hydro-gen and as much as 95% or more hydrogen.With an unsaturated Coker pressure distillate the recycle gas containsbetween about and about 50% hydrogen when catalytic cracking alone iscarried out. With saturatedfeed stocks, that is, for eX- arnple, astraight-run gas oil, the .recycle gas contains from to 80% hydrogen.When the principles of this process are applied to thermal contactcoking of heavy oils, the recycle gas desirably contains lesshydrogenand may be treated for hydrogen removal. It may bepredominatelymethane and lower boiling hydrocarbon gases. The operationpressures may vary-within wide ranges such-as from atmosphericto about5000,-p. s. i. g. With straight catalytic cracking,`pressures of theorder of above p. s. i. g. arepreferredsince increased liquid yields anddecreased coke laydown -is obtained.` Pressures between about 100 p. s.i. g. and Z50-p. s. i. g. are very effective. However,v pressures ashigh Yas about 600 p. s. i. g. maybe employed. When desulfurization oraromatization o-r hydrogenation are desired, higher operating pressuresare preferable such as between about 500 p. sti. g; and 2000 p. s. i.g., with pressures of the order of 100G-p. s. i. g. to 1500p. s. i. g.being preferred.

Operation temperatures again vary depending upon the process and the`feedstock. -In general, catalysts are-'in-v troduced into -the reactor.at temperatures between yabout 800 and 1200 F. and preferably of theorder of from 100 F. to as high as 600 F. above the temperature atwhichthe reactor feed is introduced. In straight catalytic cracking,temperatures of between about atmospheric and about 750 F. maybeemployed for the inletl feed'fternperature. Preferably, the reactor feedis introduced at about700 F. with the cracking catalyst; en-q tering atfrom about 700 F. to 1000-o F.

The reactionternperatures can only `be given as averages sinceconsiderablev temperature variation occurs within:the bed ofsolids inthe reactor as Well as varying fromoneprocess to another withinlimits ofbetween.

about L50091;. and about 1100 F. With catalytic crack.

ingA preferred temperatureslie between 750 F. and. 950. F.,`Withcatalytic .reforming preferred temperaturesy lie between 800 F.and.1000 F., in desulfurizationprev ferred temperatureslie between thisyinvention, ,the reactiontemperatures are preferably between about 800Fr. and 1100 F. These average reaction temperatures are the.temperatures of the granularysolids passingthroughthe reaction zones106 and 108 .and the soaking and stripping zone 112 shown in thedrawingv and arenot necessarily the temperatures at which the feed or-solids are introduced.`

The temperature at which the hydrogen recycle gas is introducedispreferably. equal to kor somewhat higher than the average reactiontemperature vwithin the reactor. Therefore, the recycle gas is preheatedto temperatures of between about 700 F.and 1000 F. prior to beingintroduced into the reaction Zone.

The following specific examples are illustrative of the principles ofthe present invention applied to straight catalytic cracking for theproduction. of gasolinein a typical boiling point reduction process andto such a boiling point reduction process carried out simultaneously 750F. and 950 F., andv when-thermalv contact cokingv is carried outaccording fto Example 1 Data for the catalytic cracking of gas oil withsynthetic bead cracking catalyst according `to the present invention aregiven below. The feed has a 450 F. to 750 F. boiling range. The freshfeed, flowing at 10,000 barrels vper day, is combined with 20,000barrels per actor efuent is condensed and fractionated to recover astream of 400 F. and point gasoline. urne yield is obtained, thegasoline product being produced at a rate of 8100 barrels per day. Thereactor pressure ,is maintained at a value of 185 p. s. i.v g.

Example -2 A catalyticcracking process accordingk to this inventio-n maybe `carried out in Ithe manner illustrated, in

Example l by employing 540 tons per hour of acid treated naturalkr claycracking catalyst; The ygasoline yieldV is f 7900 barrels yper .dayunder substantially the samenge-y action conditions as described inExample .1.

Example 3 An aromatization and reforming'process may be carried out :inthe y'presence of a mixed reforming and cracking catalyst consisting ofa silica-alumina 4carrier containing i 10% molybdenum oxide (M003) andsynthetic-bead cat alyst as used in Example 1. .The 'recycle gas rate is2500 s. c. f./barrel. of feed,v the feed is a heavy naphthenicy gas vloil boiling between about 475 F. and 800 F.,'the aver-1 age reactiontemperature is about 950 F., land the reactor eiuent is remo-ved `at atemperatureof about 870 F. A catalyst to oil ratio on a weight basis ofabout 2 is employed.` The pressure of operation is 225 p. s. i. g.

Upon .fractionation/of the products, a 68% by volume. yield of aromaticgasoline containing 6% olens and 42% aromatics is obtained. .Asubstantial degree of aromatization thus results simultaneously with theboiling point reduction to produce'a high quality aromaticandolen vcontaining'gasoline boiling range stock.,

Example, .4 v

Comparable# results arer obtained in the process of Y Example 3 whereinan acid treated natural clay cracking catalyst'is impregnated withmolybdenum oxide 'to promote aromatization reactions.

Example 5 molybdenum oxide, the continuous desulfurization, de- ,s

nitrogenation and boiling point reduction of 850 F. end point cokerdistillate containing 1.97% by weight of sulfur and 0.10%' by weightofnitrogen is carried out. The

operating pressure is 1100 p. s. i. g. and an average reactortemperature of 860 F. is used. The recycle gas rate is 3000 s. c.f./.barrel of feed. The reactor` eiliuent is fractionated and a 64%`,yield of 410 F. endpoint gasoline is obtained containing 0.13% sulfur,and 0.005%. nitrogen. vThe catalystto oil ratio is 3.

day of oil re-v v cycle and is preheated to a temperature of 835 F.'and' contacted with 460 tons per hour of synthetic alumina; silica bead`catalyst for a catalyst to oil,ratio of about- The catalyst isintroduced at a temperature of The average reaction temperature isaboutA 860 F. The recycle gas rate is 2000 s. c. f./barrel of `feed tothe reactor. This recycle gasis preheatedftoa temperature of 900 F.prior to injection into the reactor;V`v The recycle gas contains about45% hydrogen. The re- An 81% by vol- 1 1` Example 6 Results comparableto those of Example are obtained when a mixed catalyst comprising acidtreated natural clay or synthetic bead cracking catalyst and analuminacobalt molybdate impregnated desulfurization catalyst issubstituted for the catalyst of Example 5.

Example 7 The principles of the present invention are applied to contactcoking employing a bed of petroleum coke granules averaging from 0.2inch to 0.75 inch in diameter and recirculated at 12 tons per hour. ingan A. P. I. gravity of 11 is heated to a temperature of 700 F. anddirectly contacted at a rate of 100 barrels per day with a moving bed ofcoke heated to a temperature of 1050 F. A recycle gas comprising methaneand hydrogen is countercurrently recirculated through the coking zonewhich is maintained at an average temperature of 925 F. The cokerdistillate yield is 86% by volume and contains an increased proportionof Coker gasoline due to the fact that the gasoline vapors produced areremoved very rapidly from the reaction zone in the gas recycle.

A particular embodiment of the present invention has been hereinabovedescribed in considerable detail by way of illustration and severalspecific applications of the principles of this invention have beengiven to illustrate the application of the invention in variousmodifications to a few specific processes. It should be understood thatvarious other modifications and adaptations may be made iu applyingthese same principles to other hydrocarbon conversion processes by thoseskilled in this particular art without departing from the spirit andscope of this invention as set forth in the appended claims.

I claim:

1. A process for the simultaneous boiling point reduction and catalyticconversion of hydrocarbons which comprises passing a moving compactnonuidized granular adsorptive solid catalyst bed adapted to promoteboiling point reduction and catalytic conversion of hydrocarbonsdownwardly through a reaction zone, at least partly saturating saidadsorptive catalyst with liquid hydrocarbon feed whereby said moving bedof catalyst carries said hydrocarbons adsorbed thereon at least part waythrough said reaction zone in the absence of any substantial downwardliquid flow therethrough maintaining a temperature within said reactionzone of between about 500 F. and about 1100 F., flowing a recycle gascontaining hydrogen at a rate of between about 50 s. c. f. and about10,000 s. c. f. per barrel of said hydrocarbon feed through saidreaction zone countercurrent to the flow' of catalyst therethroughwhereby hydrocarbon products of reduced boiling point vaporizing `fromthe liquid hydrocarbon phase contained on said catalyst are swept out ofsaid reaction zone in the vapor phase at a rate sufficient to preventany substantial degree of further boiling point reduction'of thehydrocarbon vapor products after vaporization from said catalyst bedwhile countercurrently contacting said products and said recycle gaswith said catalyst forming a reaction zone effluent, cooling andpartially condensing said effluent to separate normally liquid fromnormally gaseous components thereof, separating said recycle gascontaining hydrogen from the normally gaseous fraction, heating at leastpart of said recycle gas, recirculating the heated recycle gas to saidreaction zone, fractionating a fraction of the desired boiling rangefrom the normally liquid fraction of said efliuent as a liquid product,and recirculating the higher boiling fraction with said liquidhydrocarbon feed to said reaction zone for retreatment. I

2. A process according to claim 1 in combination with the step ofpassing spent catalyst from said reaction zone through a regenerationzone, contacting said catalyst therein with a regeneration gascontaining oxygen to burn Residual oil havhydrocarbonaceous depositstherefrom forming a regenerated catalyst, returning said regeneratedcatalyst to said reaction zone, conveying said catalyst between saidzones through elongated conveyance and sealing zones therebetween as amoving mass having a bulk density substantially the same as the bulkdensity of said moving bed, concurrently flowing an inert conveyancefluid through said conveyance zones to generate a. substantial pressuredifferential greater than about 0.1 p. s. i. g. per foot and convey saidcatalyst while applying a thrust force to catalyst discharging therefromto prevent iluidization, the substantial pressure differential existingacross said conveyance zones effectively sealing said reaction zone fromsaid regeneration zone.

3. A process for simultaneously cracking and catalytically convertinghydrocarbon liquids to form hydrocarbon products of lower boiling rangeand improved quality which comprises passing a moving bed of cornpactnonfluidized granular adsorptive solid cracking and hydrocarbonconversion catalyst downwardly through a reaction zone, contacting saidmoving bed of catalyst therein with a liquid stream of hydrocarbon feedin an amount controlled to at least partly saturate said catalysttherewith but insutlicient to cause any of said liquid stream to owdownwardly through said catalyst bed moving through said reaction zone,maintaining reaction zone temperatures of between about 500 F. and about1100 F., passing a countercurrent flow of hydrogen-containing recyclegas at a rate of between about 50 s. c. f. and about 10,000 s. c. f. perbarrel of said hydrocarbon feed through said reaction zone wherebycracked hydrocarbons p of decreased boiling range vaporizing from theliquid hydrocarbon feed-containing catalyst are passed therewith backthrough said reaction zone in the vapor phase countercurrent to thecatalyst ow at a rate sufficiently high to prevent substantial furthercrackingof the cracked hydrocarbon vapor and are removed therefrom as areactor effluent, cooling and partially condensing said eflluent toseparate normally liquid from normally gaseous components thereof,separating said recycle gas containing hydrogen from the normallygaseous fraction, heating at least part of said recycle gas,recirculating the heated recycle gas to said reaction zone,fractionating a fraction of the desired boiling range from the normallyliquid fraction of said effluent as a liquid product, and recirculatingthe higher boiling fraction with said liquid hydrocarbon feed to saidreaction zone for retreatment.

4. A process according to claim 3 wherein the Weight ratio of catalystto hydrocarbon feed is between about 0.5 and about 15.0, saidhydrogen-containing recycle' gas is introduced into said reaction zoneat a temperature greater than the average reaction zone temperature, thereaction zone pressure is maintained between about atmospheric and about5000 p. s. i. g., said liquid hydrocarbon feed is introduced at atemperature between about 500 F. and about 750 F., and said catalyst isintroduced into said reaction zone `at a temperature of between about F.and about 500 F. above the feed temperature.

5. A process according to claim 3 wherein the weight ratio of catalystto said hydrocarbon feed is between about 3.0 and 15, said catalyst isintroduced at a temperature between about 800 F. and about 1200 F andsaid hydrocarbon feed is introduced unheated.

6. A process according to claim 3 wherein said catalyst comprises amechanical mixture of hydrocarbon cracking catalyst and a catalyst topromote at least one other hydrocarbon conversion reaction selected fromthe group consisting of catalytic desulfurization, denitrogenation,isomerization, aromatization, hydrogenation, dehydrogenation, andreforming of hydrocarbons.

7. A process for simultaneously cracking and catalytically desulfurizinghydrocarbon liquids to form a desulfurized hydrocarbon product ofreduced boiling point which comprises passing a moving bed of compactnoniluidized bed of granular adsorptive solid cracking and hydrocarbondesulfurization-catalyst downwardly through a reaction zone, contactingsaid l lyst therein with a liquid stream of hydrocarbonf. feed to adsorbon and at least partly saturatesaid catalyst with said hydrocarbonliquid prior to movement of the thus treated catalyst bedcontaini'ngrsaid adsorbed hydrocarbon liquid through saidrreaction zone,.controlling the amount of said` feed to prevent any., substantialliquid flow downwardly through said `adsorptive catalyst bed,maintaining reaction lzonetemperatures of between about 750 IF. andabout 950 F., passing a-flow of hydrogenv containing recycle gas at arate of between about '7.50 s. c. f. and about 3000s. c. frper barrel ofsaid hydrocarbon feed .countercurrently throughsaid reaction zonewhereby cracked hydrocarbons o f decreased boiling range vaporizing fromthe liquidwhydrocarbon feed-containing catalyst are passed-therewithback through said reaction zone-in Vthe vapor'phase- ,countercurrent tothe catalyst ow Iat a rate sufficient to eliminateanyfurtherisubstantial boiling point reduction reaction and are removedtherefrom as a reactor efuent containing a reduced s'ulfur content,cooling and partially condensing said effluent to separate normallyliquid from normally gaseous components thereof, separating said recyclegas containing hydrogen from the normally gaseous fraction, heating atleast part -of said recycle gas, recirculating the heated recycle gas tosaid reaction zone, fractionating a fraction of the desired boilingrange from the normally liquid fraction of said eluent as a liquidproduct, and recirculating the higher boiling fraction with said liquidhydrocarbon feed to said reaction zone for retreatment.

8. A process according to claim 7 wherein said desulfurization catalystis selected from the group consisting of cobalt molybdate and mixturesof cobalt oxide and molybdenum trioxide.

9. A process for simultaneously cracking and catalytically reforminghydrocarbon liquids to form a reformed aromatic hydrocarbon containingproduct of reduced boiling point which comprises passing a movingcompact nonuidized bed of granular adsorptive solid cracking andhydrocarbon reforming catalyst downwardly through a reaction zone,contacting said moving bed of catalyst therein with a liquid stream ofhydrocarbon feed to adsorb on and at least partly saturate said catalystwith said hydrocarbon feed prior to movement of the thus treatedcatalyst bed containing said adsorbed hydrocarbon liquid through saidreaction zone, controlling the rate of liquid hydrocarbon introductionso as to prevent any substantial liquid ow downwardly through saidadsorptive catalyst bed, maintaining reaction zone temperatures ofbetween about 800 F. and about l000 F., passing a flow ofhydrogen-containing recycle gas at a rate of between about 1000 s. c. f.and about 4000 sc. f. per barrel of said hydrocarbon feedcountercurrently through said reaction zone whereby cracked hydrocarbonsof decreased boiling range vaporizing from the liquid hydrocarbonfeed-containing catalyst are passed therewith back through said reactionzone in the vapor phase countercurrent to the catalyst flow and areremoved therefrom as a reactor effluent containing aromatichydrocarbons, cooling and partially condensing said effluent to separatenormally liquid from normally gaseous -components thereof, separatingsaid recycle gas containing hydrogen from the normally gaseous fraction,heating at laest part of said recycle gas, recirculating the heatedrecycle gas to said reaction zone, fractionating a fraction of' thedesired boiling range from the normally liquid fraction of said eluentlas a liquid product, and recirculating the higher boiling fraction withsaid liquid hydrocarbon feed to said reaction zone for retreatment.

l0. A process according to claim 9 wherein said reforming catalyst isselected from the group consisting of molybdenum trioxide, cobaltmolybdate, chromium vmoving bed of cata-` 14 oxide, :and mixtures ofcobalt oxide and molybdenum trioxide.

l1. A process for conversion of hydrocarbons in contactI with a compactnonfluidized bed of granular adsorptive vsolids which vcomprises passinga moving bedof granular solids downwardly by gravity throughy a reactionzone, contacting said adsorptive solids with a liquid stream ofhydrocarbons to be converted whereby -said liquid hydrocarbon isadsorbed on and at least partially saturates said adsorptive solids andis carried thereby at least part way through `said reaction zone,maintaining hydrocarbon conversion conditions of pressure and tern.-v

perature within said reaction zone, and passing a countercurrent ow ofgas through said reaction zone at a sutilciently high rate to sweephydrocarbon conversion prod-" ucts of increased volatility escaping intothe vapor phase from the liquid phase associated with the solids rapidlyfrom said reaction zone without substantial further reactionthereof;

l2. A process for conversion of hydrocarbons to produce products ofreduced boiling temperature which comprises passing a moving bed ofcompact nonfluidized granular adsorptive solids downwardly by gravitythrough a reaction zone, contacting the moving bed of adsorptive solidswith a liquid stream of hydrocarbons to be converted whereby saidhydrocarbons are adsorbed thereon so as to at least partially saturatesaid adsorptive solids and be carried downwardly through said reactionzone by said moving bed in the absence of any substantial concurrentliquid ow therethrough, maintaining hydrocarbon conversion conditions oftemperature and pressure therein, and rapidly sweeping hydrocarbon vaporproducts of reduced boiling temperature vapo-rizing from said moving bedby passing a ilow of low molecular weight gas at a suiciently high ratecountercurrently through said reaction zone to prevent any substantialconversion of said hydrocarbon vapor products subsequent to theirvaporization from said moving bed of solids.

13. An improved process for the cracking of liquid hydrocarbons toproduce hydrocarbons of decreased boiling points which comprises passinga moving bed of heated noniluidized granular adsorptive solidsdownwardly by gravity through a reaction zone, contacting said solidswith a heated liquid stream of hydrocarbons to be cracked whereby saidhydrocarbons are adsorbed thereon and carried at least part way therebythrough said reaction zone, controlling the amount of said liquid streamt-o prevent any substantial liquid ow downwardly through said moving bedof adsorptive solids, maintaining hydrocarbon crackingtemperatureconditions within said reaction zone whereby cracked hydrocarbonproducts are vaporized from said solids and maintaining a sui-cientlyhigh rate of a low molecular weight recycle gas flow countercurrentlythrough said moving bed to sweep hydrocarbon vapor products rapidly fromsaid reaction zone to prevent substantial further cracking` thereof.

14. A process for catalytic cracking of hydrocarbons which comprisespassing a moving bed of nonuidized adsorptive cracking -catalystdownwardly by gravity through a reaction zone, contacting said catalystwith a controlled amount of liquid hydrocarbon feed to be crackedwhereby said liquid hydrocarbon is adsorbed on said adsorptive catalystand movement -of said catalyst carries said feed adsorbed thereondownwardly through said zone and whereby no substantial flow of saidliquid hydrocarbon through said moving bed results, maintaining atemperature of between about 750 F. and about 95.0 F. within saidreaction zone, passing between about 500 s. c. f. and about 2000 s. c.f. per barrel of feed of a hydrogen-containing recycle gas therethroughcountercurrent to said bed of catalyst at a rate sufficient to sweepcracked hydrocarbon vapors therefrom without substantial furthercracking thereof, cooling and partially condensng the reaction zoneeiuent, separating said hydrogen-containing recycle gas therefrom, andrecirculating at least part thereof to said reaction zone.

15. A process according to claim 14 wherein said liquid hydrocarbon feedis brought into contact with said catalyst substantially at the point itis introduced into said reaction zone and saidreaction zone effluent isremoved as a vapor at 'substantially the same point.

16. A process according to claim 14 wherein said reactor eiuent isremoved as a vapor at a point adjacent the point at which said catalystis introduced and said liquid hydrocarbon feed is introduced at anintermediate point within said reaction zone thereby permitting coun-References Cited in the tile of this patent UNITED STATES PATENTS2,358,879 Redcay Sept. 26, 1944 2,429,359 Kassel Oct. 2l, 1947 2,437,532Huifman Mar. 9, 1948 2,439,372 Simpson Apr. 6, 1948 2,450,753 Guyer Oct.5, 1948 2,458,109 Simpson Jan. 4, 1949 2,489,628 Evans Nov. 29, 19492,498,559 Layng et al Feb. 2,1, 1950 2,499,304 Evans Feb. 28, 19502,502,958 Johnson Apr. 4, 1950 2,561,409 Ardern yJuly 24, 1951 2,606,862Keith Aug. 12, 1952 2,684,124 Hines July 20, 1954 2,694,036 Myers Nov.9, 1954 OTHER vREFEruiNCEs carbons, vol. III, page 333.

1. A PROCESS FOR THE SIMULTANEOUS BOILING POINT REDUCTION AND CATALYTICCONVERSION OF HYDROCARBONS WHICH COMPRISES PASSING A MOVING COMPACTNONFLUIDIZED GRANULAR ADSORPTIVE SOLID CATALYST BED ADAPTED TO PROMOTEBOILING POINT REDUCTION AND CATALYTIC CONVERSION OF HYDROCARBONSDOWNWARDLY THROUGH A REACTION ZONE, AT LEAST PARTLY SATURATING SAIDADSORPTIVE CATALYST WITH LIQUID HYDROCARBON FEED WHEREBY SAID MOVING BEDOF CATALYST CARRIES SAID HYDROCARBONS BSORBED THEREON AT LEAST PART WAYTHROUGH SAID REACTION ZONE IN THE ABSENCE OF ANY SUBSTANTIAL DOWNWARDLIQUID FLOW THERETHROUGH MAINTAINING A TEMPERATURE WITHIN SAID REACTIONZONE OF BETWEEN ABOUT 500*F. AND ABOUT 1100*F., FLOWING A RECYCLE GASCONTAINING HYDROGEN AT A RATE OF BETWEEN ABOUT 50S. C. F. AND ABOUT10,000 S.C.F. PER BARRLE OF SAID HYDROCARBON FEED THROUGH SAID REACTIONZONE COUNTERCURRENT TO THE FLOW OF CATALYST THERETHROUGH WHEREBYHYDROCARBON PRODUCTS OF REDUCED BOILING POINT VAPORIZING FROM THE LIQUIDHYDROCARBON PHASE CONTAINED ON SAID CATALYST ARE SWEPT OUT OF SAIDREACTION ZONE IN THE VAPOR PHASE AT A RATE SUFFICIENT TO